code: def test_invalid_transform():
      # Note: users should not attempt to use the base class Transform:
      # they should get an instance of one of its derived classes from the
      # regtransforms dictionary (the base class is not contained there)
      # If for some reason the user instantiates it and attempts to use it,
      # however, it will raise exceptions when attempting to retrieve its
      # Jacobian, identity parameters or its matrix representation. It will
      # return -1 if queried about its dimension or number of parameters
      transform = Transform()
      theta = np.ndarray(3)
      x = np.ndarray(3)
      assert_raises(ValueError, transform.jacobian, theta, x)
      assert_raises(ValueError, transform.get_identity_parameters)
      assert_raises(ValueError, transform.param_to_matrix, theta)
  
      expected = -1
      actual = transform.get_number_of_parameters()
      assert_equal(actual, expected)
  
      actual = transform.get_dim()
      assert_equal(actual, expected)
  
file_path: dipy/dipy/align/tests/test_transforms.py
imports: import numpy
  from numpy.testing import assert_array_equal, assert_array_almost_equal, assert_equal, assert_raises
  from dipy.align.transforms import regtransforms, Transform
  from dipy.testing.decorators import set_random_number_generator
label_desc: Use image node_id 6 for calling a global function with example usage: test_invalid_transform() without return types